一个类似于windows自带的画图程序，要求用鼠标为主要的输入手 段，实现直线、多边形、圆和椭圆的绘制，有undo和redo的功能。用C++语言实现。-Similar to the windows built-in Paint program requirements with the mouse as the main means of input, line, polygon, circle and ellipse drawing, undo and redo functionality.